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| n | a(n) |
|---|---|
| 8 | 0 |
| 9 | 0 |
| 10 | 2 |
| 11 | 3 |
| 12 | 12 |
| 13 | 23 |
| 14 | 61 |
| 15 | 135 |
| 16 | 306 |
| 17 | 679 |
| 18 | 1499 |
| 19 | 3254 |
| 20 | 7041 |
| 21 | 15127 |
| 22 | 32321 |
| 23 | 68745 |
| 24 | 145654 |
| 25 | 307507 |
| 26 | 647246 |
| 27 | 1358592 |
| 28 | 2844722 |
| 29 | 5943310 |
| 30 | 12392127 |
| 31 | 25790949 |
| 32 | 53587142 |
| 33 | 111169216 |
| 34 | 230298492 |
| 35 | 476459514 |
| 36 | 984532396 |
| 37 | 2032073964 |
| 38 | 4189741347 |
| 39 | 8629836681 |
| 40 | 17758744396 |
[0,0,2,3,12,23,61,135,306,679,1499,3254,7041, 15127,32321,68745,145654,307507,647246,1358592, 2844722,5943310,12392127,25790949,53587142, 111169216,230298492,476459514,984532396, 2032073964,4189741347,8629836681,17758744396] |